Many people with these illnesses become depressed. In fact, depression is one of the most common complications of chronic illness. It's estimated that up to one-third of people with a serious medical condition have symptoms of depression.

Recommended Related to Depression

Tina Merritt, now 39, of Virginia Beach, Va., had heard of postpartum depression when she was pregnant seven years ago. But when she gave birth to her son, Graham, she expected nothing but joy as she and her husband welcomed the baby boy who would be the first grandchild on both sides of their families."It took me a while to get pregnant, and it was a huge deal for everyone," Merritt says."I worked right up to the end of my pregnancy and felt great. I'd planned so long for this baby, I really...

It's not hard to see the cause and effect relationship between chronic illness and depression. Serious illness can cause tremendous life changes and limit your mobility and independence. A chronic illness can make it impossible to do the things you enjoy, and it can eat away at your self-confidence and a sense of hope in the future. No surprise, then, that people with chronic illness often feel despair and sadness. In some cases, the physical effects of the condition itself or the side effects of medication lead to depression, too.

What Chronic Conditions Trigger Depression?

Although any illness can trigger depressed feelings, the risk of chronic illness and depression gets higher with the severity of the illness and the level of life disruption it causes. The risk of depression is generally 10-25% for women and 5-12% for men. However, people with a chronic illness face a much higher risk -- between 25-33%. Risk is especially high in someone who has a history of depression.

Depression caused by chronic disease often makes the condition worse, especially if the illness causes pain and fatigue or it limits a person's ability to interact with others. Depression can intensify pain, as well as fatigue and sluggishness. The combination of chronic illness and depression might lead you to isolate yourself, which is likely to make the depression even worse.

Research on chronic illnesses and depression indicates that depression rates are high among patients with chronic conditions: